I dont think the EXP hack works anymore:
Call of Duty: Modern Warfare 2 has been patched to 1.0.177.
# Care Package, Emergency Airdrop, and Sentry Gun marker grenades sprint speed normalized
# Sentry Guns: Improved placement detection, preventing cases of Sentry Guns inside geometry
# Model 1887: Bling using Akimbo and FMJ combination now has same range and damage as non-Bling Model 1887s
# Improved player collision removing cases of getting into geometry and 'elevators'
# Mouse latency tweaks for more mouse movement consistency
# Fixes to prevent various texture and XP hacks